How brains are wired to handle stress

The brain gets flooded with dopamine when under stress. Special enzymes in the prefrontal cortex determine responses.

Suppose you're under a lot of pressure. Does it feel like a huge flood is swirling around in your brain, tossing your thoughts every which way?

Well, Ashley Merryman and Po Bronson say, maybe that's because your brain really is flooded — with dopamine. Dopamine is a neurotransmitter that the brain needs to run at full capacity, but as with so many good things, it's possible to have too much of it. So, as your brain keeps producing fresh dopamine, it has to keep getting rid of the old. In the prefrontal cortex, special enzymes called COMT — for catechol-O-methyltransferase — carry out these mop-up operations.

The prefrontal cortex serves as the brain's central intelligence agency. It has to perform well for you to perform well, and it can perform well only if it has the right amount of dopamine.

But stress brings on a dopamine surge that can overwhelm your poor COMT enzymes if they don't act fast. And not everyone's can. In fact, there are two kinds of COMT enzymes, workaholics and slackers, and workaholics are four times faster.

If your genes gave you workaholic enzymes, stress is no sweat. You're in your element. But if your genes gave you slackers, they have trouble handling an influx of dopamine — and you have trouble handling an onslaught of stress.

Having slugabed COMT is not all bad news, though. When you're not under stress — which, let us hope, is most of the time — your lollygagging enzymes always leave enough dopamine around to keep your brain at the top of its game. On the other hand, in run-of-the-mill situations, speedy enzymes can be so overzealous that they don't leave behind enough dopamine for your brain to do its best work.